Molecular dynamics of n-dodecylammonium chloride studied by nuclear magnetic resonance
Fojud Z.1, Szczesniak E.1, Jurga K.1, Jurga S.1,2
- 1Institute of Physics, Adam Mickiewicz University, Poznań, Poland
- 2Institute of Physics, Adam Mickiewicz University, 85 Umultowska st, 61-614 Poznań, Poland
Applied Magnetic Resonance, 19, pp.413-420, 2000
DOI::
Abstract:
Abstract. The relation between molecular dynamics and phase properties of the bilayered compound C12H25NH3Cl is studied by differential scanning calorimetry, proton second moment, and spin-lattice relaxation times. In the low-temperature phase I of the compound methyl and ammonium groups execute a classical threefold reorientation, while the alkylammonium chains are rigid on the nuclear magnetic resonance time scale. In the intermediate-temperature phase δ a trans-gauche isomerization of the alkyl chains is observed. In the high-temperature phase a the reorientation of the whole chains about their long axes, which are parallel to the normal to the ionic layer is evidenced. In the meta-stable ε phase the dynamics involves classical rotation of methyl and ammonium groups and CH2 groups motion of the trans-gauche isomerization type. ©Springer-Verlag 2000.
full version of publicationshow all publications